@keyframes shake {
  0% { transform: scale(1); }
  20% { transform: scale(1.2) rotateZ(0); }
  30% { transform: scale(1.2) rotateZ(-30deg) }
  40% { transform: scale(1.2) rotateZ(30deg) }
  50% { transform: scale(1.2) rotateZ(-30deg); }
  60% { transform: scale(1.2) rotateZ(30deg); }
  70% { transform: scale(1.2) rotateZ(-30deg); }
  80% { transform: scale(1.2) rotateZ(30deg); }
  90% { transform: scale(1.2) rotateZ(0); }
  100% { transform: scale(1); }
}

.shake-animation {
  animation: shake 2s infinite;
}

